The value of the measurement from T5 to T12 as a screening tool in detecting abnormal kyphosis

Because vertebral endplates above T5 are not consistently seen on standard lateral radiographs, we assessed the reliability of measuring from T5 to T12 to detect abnormal kyphosis in children. Sixty-nine subjects were included, with 43 normal controls. Propst-Proctor and Bleck reported the normal measurement of T5-T12 to be between 20 and 33 degrees. All 69 patients with abnormal kyphosis measured > 33 degrees from T5 to T12. Twenty-four normal subjects had measurements < or = 33 degrees, and 19 measured > 33 degrees. Sensitivity, specificity, and accuracy were 100, 56, and 83%, respectively, when using 33 degrees as the upper limit of normal. In conclusion, a measurement from T5 to T12 of > 33 degrees on lateral thoracolumbar radiographs as a screening for abnormal kyphosis had a sensitivity of 100%. For patients with a measurement > 33 degrees, additional lateral radiographs to visualize the entire thoracic spine above T5 would be warranted.